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131.
Rostami Sara Toghraie Davood Esfahani Masihollah Ahmadi Hekmatifar Maboud Sina Nima 《Journal of Thermal Analysis and Calorimetry》2021,143(2):1119-1128
Journal of Thermal Analysis and Calorimetry - In the current work, after generating experimental data points for different volume fraction of nanoparticles ( $$\phi$$ ) and different temperatures,... 相似文献
132.
Behzad Soltani Navid Ahmadi Nasab 《Journal of Dispersion Science and Technology》2018,39(8):1200-1207
The intercalation of indomethacin into the interlayer gallery of layered zinc hydroxide (LZH) has been successfully executed using the simple ion exchange approaches. The synthesized intercalation compound, indomethacin-LZH nanohybrid, was characterized using PXRD, FTIR, SEM, BET, and STA. From the PXRD results, the intercalation of indomethacin anions into the interlayer gallery of LZH was successful; showing the formation of a new peak at lower 2θ with a basal spacing of 21.96?Å. FTIR analysis of the nanohybrid further supported the presence of indomethacin in the interlayer of the indomethacin-LZH nanohybrid. STA analysis confirms that the nanohybrid has higher thermal stability than pure indomethacin. The in vitro release mechanism of the indomethacin anions from the indomethacin-LZH nanohybrid showed slow release, with 95% and 78% release in phosphate buffer saline (PBS) solution at pH 4.8 and 7.4, respectively. The release behavior of indomethacin from its intercalation compounds in PBS solution at pH 4.8 and 7.4 follows the Higuchi model. In addition, the nanohybrid treated with normal fibroblast cell line shows that it reduces cell viability in a dose and time-dependent manner. This study shows that the high potential of the nanohybrid as an encapsulated material for the controlled release formulation of nonsteroidal anti-inflammatory (NASID) anions. 相似文献
133.
Sima Ahmadi Mohammad Taghi Hamed Mosavian Somayeh Heydari 《Journal of the Iranian Chemical Society》2018,15(11):2605-2614
A rapid and simple approach for the preconcentration and determination of catechin from pistachio green hull samples has been proposed by surfactant-assisted dispersive liquid–liquid microextraction followed by UV–Vis spectrophotometry (SADLLME/UV–Vis). This method involved the formation of a catechin complex with cetylpyridinium chloride (CPC) as cationic surfactant, and subsequently, DLLME was applied to extract the catechin–CPC complex into chloroform. Different parameters affected the extraction efficiency were optimized by central composite design (CCD) and response surface methodology (RSM). In optimum condition, the calibration curve was linear in the range of 0.4–5 µg mL??1 of catechin with correlation coefficient of 0.9982. The relative standard deviation based on five replicated analyses of 1 µg mL??1 catechin was 1.85%. The proposed method was successfully applied for preconcentration and determination of trace amounts of catechin in pistachio hull samples. 相似文献
134.
Maryam Mohebbi Peyman Salehi Morteza Bararjanian Samad N. Ebrahimi 《Journal of the Iranian Chemical Society》2018,15(1):47-53
In this paper, synthesis of two derivatives of noscapine and their application as organocatalysts in the asymmetric addition of diethylzinc to aromatic aldehydes is reported. The first catalyst (2) was synthesized by the reduction of lactone ring of noscapine to form the corresponding diol, and the second one (3) was prepared by tert-butyl dimethyl silylation of the primary hydroxyl group of 2. Excellent yields and high ees up to 95% were obtained by using 3 as the catalyst. To the best of our knowledge, this is the first report on the application of lactone ring opened noscapinoid compounds as organocatalysts in asymmetric reactions. 相似文献
135.
Mohammad Ghanbari Neda Mollakarimi Dastjerdi Saman Ahmadi Sanaz Moradi 《Journal of the Iranian Chemical Society》2018,15(5):1119-1131
A novel inorganic–organic nanohybrid material SBA-15@triazine/H5PW10V2O40 (SBA-15@ADMPT/H5PW10V2O40) was prepared and used as an efficient, eco-friendly, and highly recyclable catalyst for the one-pot multicomponent synthesis of multisubstituted pyridines from the reaction of aldehydes, cyclic ketones, malononitrile, and ammonium acetate with good to excellent yields (77–97%). The nanohybrid catalyst was prepared by the chemical anchoring of Keggin heteropolyacid H5PW10V2O40 onto the surface of SBA-15 mesoporous silica modified with 2-APTS -4,6-bis(3,5-dimethyl-1H-pyrazol-1-yl)-1,3,5-triazine (ADMPT) linker. Standard characterization data such as FT-IR, XRD, SEM, TEM, BET, EDX, and DTA-TGA spectroscopy confirmed that the heteropolyacid H5PW10V2O40 is well dispersed on the surface of the solid support and its structure is preserved after immobilization on the SBA-15 mesoporous silica modified with ADMPT. Furthermore, the nanocatalyst can be recovered easily and reused five times without considerable loss of catalytic activity. In general, these advantages highlight this protocol as an attractive and useful methodology, among the other methods reported in the literature, for the eco-friendly and rapid synthesis of biologically active multisubstituted pyridines. 相似文献
136.
Gholami Mohammad Reza Akbari Omid Ali Marzban Ali Toghraie Davood Shabani Gholamreza Ahmadi Sheikh Zarringhalam Majid 《Journal of Thermal Analysis and Calorimetry》2018,134(3):1611-1628
Journal of Thermal Analysis and Calorimetry - In this research, the laminar and forced flow and heat transfer of oil/multi-walled carbon nanotubes nanofluid in a microchannel have been numerically... 相似文献
137.
Sasiphimol Sawadsitang Nuttika Suwannasai Wiyada Mongkolthanaruk Peni Ahmadi 《Natural product research》2018,32(19):2260-2267
The secondary metabolites of Xylaria cf. cubensis SWUF08-86 fungus were investigated, and the chromatographic separation of the crude extracts yielded seventeen compounds. The structure elucidation by spectroscopic analysis including 1D and 2D NMR and the comparison of these data with literature, along with HREIMS spectrometry, revealed one new amino amidine derivative (1), together with five known simple cyclic dipeptide analogs, diketopiperazines (2–6) and eleven other known compounds, including one hemi-cycline (10), three aromatic derivatives (11–13), one sesquiterpene (14) and three sterols (15–17). The isolated compounds were screened for anticancer and anti-pathogenic bacterial and fungal activities. Based on this work, Xylaria cf. cubensis SWUF08-86 has proven to be a diverse secondary metabolites producer. 相似文献
138.
Joshaghani M Gholivand MB Ahmadi F 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,70(5):1073-1078
The complexation reaction between Cu(2+), Co(2+) and Ni(2+) metal cations with N,N'-bis(salicylidene)-1,2-phenylenediamine (salophen), in three nonaqueous polar solvents such as: acetonitrile (AN), dimethyl sulfoxide (DMSO), methanol (MeOH) and two binary mixtures of AN:DMSO and AN:MeOH at 25 degrees C were studied by spectrophotometric and conductometric methods. All investigated metal ions form 1:1 ML complex which their stability constants were determined and increase as Irving-Williams stability order of Co(2+)相似文献
139.
The interaction of a new derivative of thiazole orange (TO-3) with calf thymus DNA (ctDNA) has been investigated by fluorescence
and absorption spectroscopy. When TO-3 binds to ctDNA, absorption bands exhibit significant hypochromicity at low base pair/dye
ratio (BP/D ratio), and high BP/D show hyperchromicity with red shift. The spectral changes are attributed to the different
species formed between TO-3 and ctDNA in the titration course of the dye molecule with DNA. Multivariate curve resolutions–alternating
least squares (MCR–ALS) is applied to the absorption measurements recorded to recover the concentration profiles and the pure
spectra of the DNA/TO-3 complexes involved in the process. The binding constant and size of the binding site have been determined
spectrophotometrically using the McGhee von Hippel equation. MCR–ALS has been used to reveal the precise concentration profiles
of all detectable species formed between ctDNA and TO-3 and their pure spectral profiles. 相似文献
140.
Shuo Chen Lijuan Wang Lei Yang Abdus Samad Rana Chuanglong He 《Macromolecular bioscience》2023,23(12):2300223
Organoid is an emerging frontier technology in the field of life science, in which pluripotent stem cells or tissue-derived differentiated/progenitor cells form 3D structures according to their multi-directional differentiation potential and self-assembly ability. Nowadays, although various types of organoids are widely investigated, their construction is still complicated in operation, uncertain in yield, and poor in reproducibility for the structure and function of native organs. Constructing a biomimetic microenvironment for stem cell proliferation and differentiation in vitro is recognized as a key to driving this field. This review reviews the recent development of engineered biomimetic microenvironments for organoids. First, the composition of the matrix for organoid culture is summarized. Then, strategies for engineering the microenvironment from biophysical, biochemical, and cellular perspectives are discussed in detail. Subsequently, the newly developed monitoring technologies are also reviewed. Finally, a brief conclusion and outlook are presented for the inspiration of future research. 相似文献